# stack-auth

Source: https://startwithidentity.com/vendors/open-source/stack-auth/
Last updated: 2026-06-19
License: content by Start with Identity. Cite the source URL.

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## Overview

Stack Auth is a young open-source authentication and user-management platform, launched in 2023 and positioned explicitly as a self-hostable alternative to managed providers like Clerk. It targets startups and product teams building on React and Next.js who want modern auth components without locking their user data into a proprietary cloud. It follows the open-core pattern: the core is open source and self-hostable, with a managed cloud tier for teams that prefer not to run it.

## What it is good at

Developer experience for the React and Next.js stack is the strength. Stack Auth ships prebuilt UI components, hooks, and a clean SDK that get sign-in, sessions, and account management working quickly. It includes B2B features such as organizations, teams, and role assignment that many lightweight auth libraries lack. The option to self-host means you can keep user data on your own infrastructure and avoid per-user pricing as you scale.

## Where it falls short

It is new. The ecosystem, third-party integrations, and production references are still building, and there is little enterprise track record to point to. Governance, audit, and compliance tooling are light compared with established platforms. Coverage outside the React and Next.js world is thinner than framework-agnostic options like [Better Auth](https://startwithidentity.com/vendors/open-source/better-auth/). For high-assurance or heavily regulated deployments, a more mature platform is the safer call.

## Pricing

The core is free and open source, self-hostable at no license cost. Stack Auth Cloud is a managed, usage-based tier. Compare the self-host versus managed math with the [TCO calculator](https://startwithidentity.com/tools/tco-calculator/).

## Best for, and who should look elsewhere

A strong fit for React and Next.js teams who want an open-source Clerk alternative with B2B features and the freedom to self-host. Look elsewhere if you need a long enterprise track record, deep governance, or a managed-only service with vendor SLAs. Teams wanting a broader CIAM should also weigh [Logto](https://startwithidentity.com/vendors/open-source/logto/) and [Zitadel](https://startwithidentity.com/vendors/open-source/zitadel/).

## Bottom line

A promising, developer-friendly open-source auth platform for modern React and Next.js products willing to bet on a young but fast-moving project.